Direct fit MedGraphics, MicroMedical, MIR Spiro Lab, MIR Spiro Doc, MIR SpiroBank, MIR MiniSpir, peak flow meters, Viasys, Vyaire, Jeager & QRS SpiroCard

External Diameter (right)- Slight Taper from 33mm to 32mm

Internal Diameter (right)- 29mm

External Diameter (left)- 28.5mm

Internal Diameter (left)- 25mm